How Do Sharks and Rays Use Electricity to Find Hidden Prey? | Deep Look

When it comes to spotting prey, sharks and rays have a secret sense beyond sight and smell. Tiny goo-filled organs called Ampullae of Lorenzini detect the invisible electric fields produced by all living creatures.

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How do Sharks and Rays Sense Electric Fields?

Most animals don’t have the ability to detect electric fields. But sharks, rays, skates and sawfish — members of a group called Elasmobranchii — are masters of detecting electric signals. It’s one of their defining features. Elasmobranchs have specialized organs called Ampullae of Lorenzini. These tiny structures allow them to home in on weak bioelectric fields generated by nearby prey.

Elasmobranch’s electrosensory organs are named after a 17th century Italian physician, Stefano Lorenzini, who first identified them while dissecting an electric ray. Lorenzini noticed dozens of tiny pores around the animal’s mouth. Each of the pores led to jelly-filled canals that ended in pocket-like structures that he called ampullae, the Latin word for a type of round-bottomed flask.

Animals emit low frequency electric fields due to a process known as osmoregulation. This process allows the concentration of ions (charged atoms or molecules) to flow between the inside of our bodies and the outside. In order for our cells to stay intact, the flow of ions needs to be balanced.

But balanced doesn’t necessarily mean equal. The concentration of ions within a shrimp’s body is much lower than that of the sea water it swims in. Their voltage, or potential difference generated between the two concentrations across “leaky” surfaces, can then be detected by the ampullae.

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[margaretteragram]

People can have magnets implanted in their fingers which allow them to physically feel electric fields. They're not super sensitive but you can feel the fields around appliances and chargers, for example, or determine whether an item is magnetic.

[observingrogue]

So this is why sharks chew undersea cables?

[ramgowda]

For us it's just a short video but behind this it's a huge hard work, many people's, lot of time,
Thanks for all your

[benbennit]

These forms of life experience and measure a very different universe from us.

[guivecchi]

Gorgeous and awesome video, like always! Keep the good quality, your videos are incredible!

[josephnoeske]

I read a study on this exact thing. The ampullae are filled with a gel that acts as a thermo-electric semi-conductor. This means that As electric fields affect the fluid, it heats and expands ever so slightly, and that is how the sharks can "feel" electricity. The shark feels the expansion and heat from the semi-conductor that fills the ampullae.

[Angel-fegs]

Your work is really incredible, amazing, I love it; one of the best channels I've found, the music fits really well with every situation, the narrative is nice to listen and the best is the incredible scenes and macro shots in every single video. Thank you for this really good work.

[polari]

"None of this explains what it's like to feel electricity"
This feel like lightning strike envy to anyone else?

[andrewpotapenkoff]

Feeling electricity is like feeling warmth, i guess.

[kieungan]

This is really beneficial to visualize and simplify the Ielts listening test, part 4 as it is mostly about popular science, the hardest section to achieve expected points. This test is becoming increasingly popular in Vietnam.

[ironmountain]

This channel is really a gem on YouTube, great content!

[leilanidababe]

If you had taught me in science class I wouldve probably learned more

[juxtra]

I learned about ampulae from Endless Ocean 2. It's a shame those games weren't more popular. They were so informative!

[inkedseahear]

I love it when the second they flipped the switch the Ray immediately lamps on the spot. Or was it just nice editing, either way it's halirous

[Drunk_Bishop]

I wish there were more subscribers. i guess i can share this around. i really love the vivid style thats done here

[stickfigtree]

What strikes me as fascinating is how the ampulae remind me of an eye. Socket filled with a jelly like medium and lined with electro-sensitive cells. It's almost like they see the electric pulses as blinking beacons.

[Buckets]

The colour spectrum is just the increasing (or decreasing) wavelength/frequency of EM waves. Maybe these Elasmobranchs have different colours for electricity.

Also the most interesting part is that when a human senses something from afar, the receptors are densely packed into organs (retina, eardrum, nasal membrane) but our skin has receptors all over giving us a more tactile experience to things that we can touch.

Since the electro receptors are spread across the body, does that mean the animal 'feels' the electricity in the way we feel objects? Does it feel like they are touching everything nearby without actually coming into contact with it?

[bloodlxlart]

Why don’t they study an electric field that deters sharks and make it a wristband for surfers

[Itsjustvideos]

I just want to say... I subscribed in 2017... but now I'm going back to watch all your content because of how amazing they are! and yes... I am spreading the word!

[jaZZfanaticable]

HIGH QUALITY VIDEOS GUYS! love your content